Adjusting joint for pliers or the like



July E96? D. T. MILES ETAL ADJUSTING JOINT FOR PLIERS OR THE LIKE Filed OOC. 23, 1965 para, 5:

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3,33il,l32 Patented July 18, 1967 .Hice

ABSTRACT F' THE DISCLOSURE An adjustable joint for tools of the type having relatively pivoting paws. The joint includes a pivot pin that is nonrotatably fitted to one jaw and serves as a bearing for the other jaw. The jaw that is freely pivotal on the pivot pin is formed with one or more abutment bosses which engage flats on the pivot pin to limit the extent of its pivot-al movement.

This invention relates to tools such as pliers, cutters, and the like, and particularly to a tool having an adjustable pivoting joint.

In the manufacture of cutting pliers and similar hand tools, the provision of a smoothly operating yet tight joint has posed a constant problem. If a permanent rivet is used for the pivot pin, the joint is frequently too tight fitting when the tool is new. On the other hand, if the joint is made sufficiently loose fitting as to operate with ease when new, it will become excessively loose as soon as any wear develops in the parts. If a common nut and bolt are used for connecting the relatively pivoted members of the tool, the joint will tend to become loose and sloppy with great frequency as a result of the nut unthreading on the bolt, thereby causing the tool to malfunction. While various adjustable pivoting joints have been proposed, such devices have generally been extremely bulky and they have been unsatisfactory in other respects. Accordingly, it is an object of the present invention to provide a tool having an adjustable pivot joint in which the pivoted members are secured on a pivot pin or the like by a fastener which can be easily adjusted but which will tend to remain in its adjusted position and will not require frequent tightening.

It is another object of the present invention to provide a tool of the above character in which the degree of pivotal movement of the relatively pivoting members is controlled by means incorporated within the joint and excessive pivotal movement is avoided.

It is another object of the present invention to provide a joint for a hand tool or the like which is compact and may be totally recessed within the opposing faces of the members to be pivoted, which is inexpensive, which is sturdy in construction, which is easily assembled, and which is easily serviced.

These and other objects of the invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings, wherein:

FIGURE 1 is a plan view with parts broken away of a pair of cutting pliers incorporating the present invention;

FIG. 2 is a sectional view of the structure illustrated in FIG. 1 taken along the line 2 2 thereof; and

FIGS. 3 and 4 are sectional Views of the structure illustrated in FIG. 2 taken along the lines 3 3 and 4 4 thereof, respectively.

While the present invention has application to a wide variety of tools having pivoting joints, the invention is illustrated herein in conjunction with a pair of cutting pliers having a pair of cutting jaws 5 and 6. The jaws 5 and 6 are integrally formed with handles 7 and 8, respectively. The member consisting of the jaw 5 and its handle 7 is in crossed relationship with the member consisting of the jaw 6 and its handle 8. By this means said members are conveniently pivotally united and when the handles 7 and 8 are closed the jaws 5 and 6 will close. For the sake of convenience in the following description, reference will be made to the jaws 5 and 6 as being pivoted, although it will be appreciated that the pivoted structure includes the entire members of which the jaws 5 and 6 form parts. The joint for the jaws 5 and 6 includes a pivot pin ory nut member 9 and a cap screw or bolt 10 threaded into the pin 9. The pivot pin 9 passes through an opening 11 formed in the jaw 5 and an opening 12 formed in the jaw 6. The jaw 5 is formed with a counterbore 13 at one end of the opening 11 and the jaw 6 is formed with a counterbore 14 at one end of the opening 12. The counterbores 13 and 14 are disposed on the outside surfaces of the jaws 5 and 6 as the jaws 5 and 6 are assembled.

The screw 10 is formed with an enlarged head 15 of relatively short axial length which seats in the counterbore 14 so that its outer surface is Iflush with the outer surface of the jaw 6. The head 15 has a flat radially extending annular shoulder 16 which seats against the bottom of the counterbore 14.

The pivot pin 9 is formed with a large head or radially extending annular ilange 17 at one end thereof having a flat annular shoulder 18 engageable with the jaw 5 at the bottom of its counterbore 13. The flange 17 of the pivot pin 9 and the head 15 of the screw 10 cooperate to hold the jaws 5 and 6 in engagement. The screw 10 is adjusted so that the jaws 5 and 6 will be held together firmly but not so tightly as to interfere with the ability of the jaws to pivot relative to one another.

The pivot pin 9 is provided with a hollow tubular shank portion 19 extending from the flange 17 to the end of the pivot pin 9 opposite the head 17. The shank portion 19 is of a uniform cross-sectional shape throughout its length, such shape being illustrated in FIGS. 3 and 4. By reference to said views, it will be seen that the periphery of the shank portion 19 is provided with a pair of opposite segmentally circular cylindrical surfaces 20 which are separated by a pair of opposite parallel flat abutment surfaces 21. The sh-ank portion 19 has a threaded bore 22 extending axially throughout almost its entire length. The shank 19 has a hole drilled transversely inwardly from one of the flat surfaces 21 to the bore 20 and this bore has a nylon plug 23 press-lit therein. The nylon plug 23 projects into the area of the threads of the bore 22 and will frictionally bind against the threads of the screw 19 as it is threaded into the bore 22. By this means definite torque is required to produce rotation of the screw 10 and inadvertent or accidental loosening of the screw 10 from its intended position is prevented.

Turning particularly to FIG. 4, it will be seen that the opening 12 in the jaw 6 is provided with a pair of opposite flat surfaces 24 conformably engageable with the liat surfaces 21 of the pivot pin 9 and with a pair of segmentally circular cylindrical surfaces 25 engageable with the segmentally circular cylindrical surfaces 20 of the pivot pin 9. In other words, the opening 12 of the jaw 6 has a cross-sectional shape substantially identical to and conformably engaging the shank portion 19 of the pivot pin 9. Therefore, the jaw 6 is nonrotatable with respect to the pivot pin 9.

The opening 11 of the jaw 5 is segmentally circular cylindrical to conformably engage the segmentally circular cylindrical portions 20 of the pivot pin 9. The pin 9, therefore, forms a journal support for the jaw 5, which smoothly pivots on the pin 9 about its longitudinal axis. The opening 11 has a pair of opposite bosses 26 projectin gradially inwardly thereof. Each boss 26 has an abutment surface 27 that ist engageable with one of the adjacent flat surfaces 21 of the pivot pin 9 to limit the degree of opening pivotal movement of the jaws and 6. This assures that the arms 7 and 8 will not pivot so far apart from one another that a spring 29, which is seated in a pair of recesses 30 formed in the arms 7 and 8, will fall out of said recesses. Furthermore, the provision of a firm stop for limiting the degree of opening movement of the jaws 5 and 6 renders the pliers substantially more convenient to use even when a spring 29 is not employed.

It will be seen that the head 15 of the screw 10 has a slot 28 for the reception of a screw driver by means of which the screw may be adjusted to the desired position. No tool-receiving slot is required in the pivot pin 9 inasmuch as pivot pin 9 is held against rotation during adjustment of the screw 10 by virtue of its nonrotating fit in the jaw 6.

It is significant to note that the pivot pin 9 and screw head 10 do not project beyond the outer surfaces of the jaws 5 and 6, respectively. The outer surface of the screw head is ush with the outer surface of the jaw 6 and the outer surface of the ange 19 of the pivot pin 9 is flush with the outer surface of the jaw 5. This is believed to constitute -a substantial improvement over various bulky constructions heretofore proposed wherein a bolt is projected through theintertting members and a nut, seated against the outer surfaces of one of the members, is threaded onto the bolt.

In the construction of the present invention the screw 10 is insulated from any rotational forces tending to unthread it from the pivot pin 9. This results from the fact that the jaw 6, which the head of the screw 10 engages, is held against rotation with respect to the pivot pin 9 and insulates the head 15 of the screw 10 from the angular movement of the jaw 5. The pivot pin tiange 17 is integral with the shank portion 19 and, of course, cannot turn with respect to the shank portion 19. Accordingly, there are no positive rotational forces acting on the screw 10 and pivot pin 9 tending to unthread them and the frictional contact of the plug 23 with the threads of the screw 10 are sufficient to hold the screw 10 in any desired adjusted position. Should it ever become necessary to adjust the position of the screw 10, as a result of wear of parts, or for any other reason, the slot 28 of the screw is immediately available for the reception of a screwdriver by means of which such as adjustment can be rapidly and conveniently accomplished. Furthermore, it will be noted that in the construction of the present invention, the head 15 of the screw 10 and the counterbore 14 has a diameter which is slightly larger than the diameter of the ange 17 and the counterbore 13. Accordingly, any reversal in positions of the head 15 and flange 17 by improper assembly is prevented and the pivot pin 9 cannot be accidentally inserted into the holes 11 and 12 from the wrong side.

While it will be apparent that the preferred embodiment of the invention illustrated herein is well calculated to fulfill the objects above stated, it will be apparent that the invention is susceptible of modication, variation and change without departing from the fair meansing or the scope of the subjoined claims.

What is claimed is:

1. A pair of relatively pivoting members having aligned openings extending therethrough; a pivot pin having a shank portion disposediin said openings, a head on one end of said shank portion engageable with one of said members and a threaded bore extending inwardly from the other end of said shank portion; a screw threaded into said bore and having a head engageable with the other of said members; said shank portion being provided with opposed segmentally circular cylindrical surfaces and opposed flat surfaces; one of said members engaging said flat surface to prevent any rotation thereof on said shank portion and the other of said members being journaled on said shank portion of segmentally cire cular cylindrical surfaces; said other member having bosses extending radially into the opening thereof engageable with the liat surfaces of said shank portion to limit relative pivoting movement of said members in at least one direction.

2. A tool including a pair of relatively pivoting memi bers provided with aligned openings extending therethrough, a pivot pin having a head engageable with one of said members and a shank disposed in said openings, said shank having an outer periphery which is of substantially uniform shape over its entire length, said outer periphery being provided with-a cylindrical surface and a noncylindrical abutment surface, the opening of one of said members being shaped to nonrotatably t said one member to said shank and the opening of the other of said members being partly defined by a cylindrical surface conformably engaging the cylindrical surface of said shank whereby the cylindrical surface of said shank forms a bearing for said other member, said other member having an abutment surface adjacent the opening thereof engageable with said shank abutment surface to limit the extent of pivotal movement of said other member upon said shank in one direction and a threaded fastener connected to the end of said shank opposite from said head and cooper-ating with said head to confine said members therebetween.

References Cited UNITED STATES PATENTS 927,058 7/ 1909 Krouse 30-266 X 1,545,211 7/1925 Storz 30-266 1,891,865 12/1932 Beck 30-266 X 2,204,071 6/ 1940 Dalley 30-266 X 3,157,894 11/1964 Wallace 151-7 X WILLIAM FELDMAN, Primary Examiner.

J. C. PETERS, Assistant Examiner.

UNITED STATES PATENT oEEICE CERTIFICATE 0E CORRECTION Patent No. 3,331,132 Ju1y 18, 1967 David T. Miles et al.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent Should read as corrected below.

Column l line l2 for "paws" read jaws column 2 line 49, for "19" read l0 line 72, for "ist" read is column 3, line 49, for "has" read have column 4, line 3, for "meansing" read meaning line ZO, after "radially" insert inwardly Signed and sealed this 18th day of June 1968.

(SEAL) Attest:

EDWARD J. BRENNER Commissioner of Patents Edward M. Fletcher, Jr.

Aggesting Officer 

2. A TOOL INCLUDING A PAIR OF RELATIVELY PIVOTING MEMBERS PROVIDED WITH ALIGNED OPENINGS EXTENDING THERETHROUGH, A PIVOT PIN HAVING A HEAD ENGAGEABLE WITH ONE OF SAID MEMBERS AND A SHANK DISPOSED IN SAID OPENINGS, SAID SHANK HAVING AN OUTER PERIPHERY WHICH IS OF SUBSTANTIALLY UNIFORM SHAPE OVER ITS ENTIRE LENGTH, SAID OUTER PERIPHERY BEING PROVIDED WITH A CYLINDRICAL SURFACE AND A NONCYLINDRICAL ABUTMENT SURFACE, THE OPENING OF ONE OF SAID MEMBERS BEING SHAPED TO NONROTATABLY FIT SAID ONE MEMBER TO SAID SHANK AND THE OPENING OF THE OTHER OF SAID MEMBERS BEING PARTLY DEFINED BY A CYLINDRICAL SURFACE CONFORMABLY ENGAGING THE CYLINDRICAL SURFACE OF SAID SHANK WHEREBY THE CYLINDRICAL SURFACE OF SAID SHANK FORMS A BEARING FOR SAID OTHER MEMBER, SAID OTHER MEMBER HAVING AN ABUTMENT SURFACE ADJACENT THE OPENING THEREOF ENGAGEABLE WITH SAID SHANK ABUTMENT SURFACE TO LIMIT THE EXTENT OF PIVOTAL MOVEMENT OF SAID OTHER MEMBER UPON SAID SHANK IN ONE DIRECTION AND A THREADED FASTENER CONNECTED TO THE END OF SAID SHANK OPPOSITE FROM SAID HEAD AND COOPERATING WITH SAID HEAD TO CONFINE SAID MEMBERS THEREBETWEEN. 